K. B. Ignatov* and V. M. Kramarov

Received April 4, 2008; Revision received June 19, 2008
Bacterial NAD-dependent Taq and Tth DNA ligases are capable of
significantly increasing the yield of long PCR products when the
amplification is carried out using bacterial family A DNA polymerases,
e.g. Taq or Tth DNA polymerases, or with enzymatic blends containing
these polymerases. We also show that Taq and Tth DNA ligases improve
the results of PCR in the absence of NAD and therefore in the absence
of DNA ligase activity. These observations suggest that bacterial DNA
ligases can interact with these DNA polymerases, presumably as
accessory proteins, thereby enhancing the efficiency of DNA
polymerization.
KEY WORDS: long PCR, Taq DNA polymerase, Taq DNA ligase